CN116204977A - A vehicle simulation model modeling method and examination judgment method - Google Patents

Abstract

The invention provides a vehicle simulation model modeling method, namely an examination judging method, which comprises the following steps: acquiring actual parameters of the test vehicle, and modeling according to the actual data; importing the modeled vehicle model into a Unity3D project, and adding an automobile component to the model; setting automobile starting parameters, gear parameters, power system parameters, automobile state parameters, engine parameters, wind resistance calculation parameters and input coefficients for a vehicle model added with automobile components, simultaneously rewriting the applied drive and CarSpeed methods of the Unity3D to calculate the torque and the speed of the vehicle model, and then obtaining an examination vehicle simulation model. Compared with the prior art, the simulation method and the simulation device for the test vehicle realize the simulation of the test vehicle by establishing the simulation model of the test vehicle and setting corresponding parameters for the simulation model according to the specific data of the actual test vehicle, and the generated model is finer, so that the simulation result obtained by the simulation test is more accurate and the simulation effect is better.

Description

A vehicle simulation model modeling method and examination judgment method

technical field

The invention relates to the field of vehicle simulation examinations, and more specifically, to a vehicle simulation model modeling method and a test judgment method.

Background technique

With the development of science and technology and the advancement of the Internet, people can obtain a lot of information through the Internet, but there are still many technical knowledge that people need to master by actual operation, including car driving technology. For the driving license test, although the first-class theoretical knowledge of the subject can be learned through the Internet, but for the second-class and third-class practical exams, it is necessary to go to the test site for practical training, which makes it impossible to train anytime and anywhere. waste time. Now, although there are many online mock test simulation training equipment, but in many online mock test training equipment systems, the modeling of the test vehicle and the simulation of vehicle driving are not accurate enough, and the simulation of the test site is not accurate enough. It is not accurate enough, and the judgment of the test is also very inaccurate, resulting in many problems in actual operation even after online equipment training.

Contents of the invention

The present invention aims to overcome at least one defect of the above-mentioned prior art, and provides a vehicle simulation model modeling method and a test judgment method, which are used to solve the problems of inaccurate online simulation test training model and inaccurate test judgment.

The technical scheme that the present invention takes is:

A vehicle simulation model modeling method is provided, the modeling method comprising:

S1: Obtain the actual parameters of the test vehicle, and perform modeling according to the actual data;

S2: Import the modeled vehicle model into the Unity3D project, and add car components to it;

S3: Set the vehicle start parameters, gear parameters, power system parameters, vehicle state parameters, engine parameters and input coefficients for the vehicle model with the vehicle components added;

S4: Set a speed calculation related method for the vehicle model according to the parameters set in step S3, and obtain a test vehicle simulation model.

Modeling is carried out by obtaining the actual data of the test vehicle, and various detailed parameters are set for the model in Unity3D to make the established test vehicle simulation model more refined, so that the test vehicle simulation model can be used to simulate driving. The driving data is more accurate.

Further, the vehicle components in the step S2 include: wheel colliders, common colliders and rigid body components;

Adding a wheel collider specifically includes: adding WheelCollider wheel collision components to the wheels of the vehicle model in Unity3D;

Adding a common collider specifically includes: adding four spherical colliders of the front, rear, left and right of the car to the vehicle model in Unity3D, and adding a square collider of the body;

Adding a rigid body component specifically includes: adding a Rigidbody rigid body component to the vehicle model in Unity3D, setting the value of the mass Mass parameter according to the actual parameter data of the test vehicle, and checking the UseGravity application gravity option of the Rigidbody rigid body component.

Add corresponding part colliders to the vehicle model to simulate the vehicle, making the vehicle simulation more refined. At the same time, add rigid body components and use the actual parameters of the actual test vehicle, specifically the vehicle weight to set the value of the Mass parameter, and use the gravity option to simulate the weight of the vehicle, further improving the fineness of the vehicle simulation, making the simulated data more accurate and reality.

Further, the vehicle starting parameters in the step S3 include: power off state, power on state and starting car state;

And/or, the gear parameters include: manual gear parameters and automatic gear parameters;

Wherein, the manual gear parameters include: neutral gear, first gear, second gear, third gear, fourth gear, fifth gear and reverse gear, and the automatic gear parameters include: parking gear, forward gear and reverse gear;

And/or, the power system parameters include: maximum wheel deviation angle, transmission efficiency, brake pedal torque and braking curve;

And/or, the vehicle state parameters include: gear ratio of each gear, wheel torque, minimum speed and maximum speed of each gear of the vehicle, idle speed of each gear of the vehicle and foot brake torque;

And/or, the car engine parameters include: maximum engine speed, minimum engine speed, relationship curve between speed and output power, curve speed ratio, idling torque, speed increase limit, speed drop limit, downshift deceleration acceleration, engine to wheel Torque conversion factor;

And/or, the input coefficients include: steering wheel input, clutch input, brake input, accelerator input and handbrake switch.

For each part that needs to be calculated, specific parameters are set in detail. Through these detailed parameters, the calculation of vehicle motion is more accurate, and the simulated vehicle is more realistic. Among them, the vehicle starting parameters, gear parameters and input coefficients need to be obtained by matching with external equipment, and the power system parameters, vehicle state parameters and vehicle engine parameters are obtained based on the actual data of the vehicle.

Further, the speed calculation related method in the step S3 includes the ApplyDrive method;

The ApplyDrive method is specifically:

When the current vehicle speed is less than the minimum speed of the current gear, the current torque of the vehicle is calculated, the current torque of the vehicle is evenly distributed to the driving wheels to obtain the forward torque of each driving wheel, and the rigid body speed of the vehicle is calculated according to the forward torque;

The driving wheels are the wheels that the vehicle actually drives the vehicle forward;

The vehicle rigid body velocity is the theoretical velocity of the vehicle model.

Further, the calculation of the current torque of the vehicle is specifically:

The current torque of the vehicle = idling torque * current gear ratio * transmission efficiency * clutch input + torque at the current engine speed * throttle input * clutch input * transmission efficiency;

The torque at the current engine speed is calculated according to the vehicle engine parameters.

The current vehicle speed is initially set to 0 when the vehicle model is not started;

The idling torque, current gear ratio, transmission efficiency, etc. in the specific calculation are obtained according to the actual parameters of the test vehicle, and the specific conditions of the actual vehicle can be considered in the specific calculation to achieve a more realistic simulation effect. The vehicle rigid body speed is the theoretical speed of the vehicle model. When the vehicle is not started, it needs to be calculated according to the torque of the wheels to obtain the initial vehicle rigid body speed, which is the starting speed of the vehicle, and then it will be synchronized during the gradual increase. Update the vehicle rigidbody velocity.

Further, the speed calculation related method in the step S3 also includes the CarSpeed method;

The CarSpeed method is specifically:

Obtain the normalization of the vehicle rigid body velocity;

Calculating the minimum speed limit of the current gear position, the minimum speed limit of the current gear position=(maximum speed of the current gear position-minimum speed of the current gear position)*throttle input+idle speed of the current gear position;

When the value of the rigid body speed of the vehicle is greater than the maximum speed of the current gear, the current vehicle speed is calculated, specifically:

The current vehicle speed = the maximum speed of the current gear * the normalization of the vehicle rigid body speed; and update the vehicle rigid body speed to the current vehicle speed;

When the value of the rigid body speed of the vehicle is greater than the minimum speed limit of the current gear and less than the maximum speed of the current gear, the intermediate speed speedVal is defined, and the calculation formula of the speedVal is: vehicle rigid body speed value-downshift deceleration acceleration*time; Said time is the interval from the last frame to the current frame, and the unit is second; the current vehicle speed=value when speedVal is greater than 0*the normalization of the vehicle rigid body speed; and update the vehicle rigid body speed to be the current vehicle speed;

Then calculate the current normalized speed of the vehicle, specifically, the normalized speed of the vehicle*3.6, and normalize the current speed of the vehicle into a unit of km/h. The normalized method to obtain the vehicle rigid body speed is to use the normalized method in Unity3D to normalize the vehicle rigid body speed into a vector with direction, then calculate the current vehicle speed obtained by normalizing the vehicle rigid body speed Same direction as the vehicle rigid body velocity. At the same time, since the previous time calculation unit is seconds, and the vehicle speed unit is usually km/h, it is necessary to standardize the current vehicle speed after calculation, and convert the current vehicle speed unit to km/h to obtain the vehicle The current normalized velocity. In addition, in order to simulate the driving process of the vehicle, a minimum speed limit of the current gear is defined, and the calculation formula of the minimum speed limit of the current gear is: minimum speed limit of the current gear = (maximum speed of the current gear - minimum speed of the current gear) *Throttle input + current gear idle speed, that is to say, when there is no throttle input, the rigid body speed of the vehicle model will decrease, but it will be limited to the current gear idle speed due to the minimum speed limit of the current gear, and when there is throttle When inputting, even if the vehicle model decelerates, the speed of the rigid body decreases, and it will be limited to the minimum: (maximum speed of the current gear - minimum speed of the current gear) * throttle input + idle speed of the current gear.

The present invention also provides a method for judging a vehicle simulation test, using the test vehicle simulation model established by the above-mentioned vehicle simulation model modeling method, the method comprising:

A1: Create an initial test scene model based on the real test scene and import it into Unity3D;

A2: use the vehicle simulation model modeling method to establish a test vehicle simulation model according to the information of the test vehicle;

A3: According to different test items, set the rules of the test items;

A4: Set rule triggers and judgment rules for the initial test scenario model according to the rules of the test item, and generate a simulated test scenario model;

A5: Import the simulated test scene model and the test vehicle simulation model with set rule triggers and judgment rules into the external car simulation equipment system, and match the test vehicle simulation model with the operating equipment in the car simulation device to establish The conversion rules of the operation data of the operation equipment and the simulation data of the test vehicle simulation model;

A6: The terminal user inputs the operation data through the operation device, and the vehicle simulation device converts the operation data into the simulation data of the test vehicle simulation model according to the conversion rule;

A7: The car simulation device drives the test vehicle simulation model to run in the simulated test scene model according to the simulated data, and judges the result according to the rule trigger and the judgment rule.

By using the real test scene to establish the initial scene model, the simulated test can restore the realistic test environment as much as possible, and obtain a more realistic sense of presence and reality. And according to the test items, set rule triggers and judgment rules for the initial scene model to obtain the simulation scene model, and import the set test vehicle simulation model to the car simulation device at the same time. Various parameters have been set in the car simulation model. Car simulation The equipment is equipped with various operating equipment required for driving simulation, such as steering wheel and accelerator, etc. These operating equipment are matched with the vehicle simulation model, and conversion rules are established for the operation data input by the operating equipment and the simulation data of the test vehicle simulation model , such as the rotation angle of the steering wheel of the operating device and the steering wheel input conversion rules of the test vehicle simulation model; after the rules are established, the operation data can be sent to the vehicle simulation device by operating the operation device, and then the vehicle simulation device converts the test data according to the operation data. The simulation data of the vehicle simulation model, the test vehicle simulation model performs simulated driving in the simulated test scene model according to the simulated data, and then judges the score of the end user according to the judgment rules based on the data fed back by the rule trigger during the driving process. By setting the test vehicle simulation model with various parameters in detail, and setting a set of conversion rules with the vehicle simulation equipment, the judgment standard of the simulation test is more detailed and the obtained results are more accurate.

Further, the establishment of the initial test scene model according to the real test scene is specifically:

Sampling the actual test scene through aerial photography modeling or oblique photography technology, and using Maya3D to process and optimize the sampling results to obtain the initial test scene model consistent with the actual scene environment layout.

The actual test room is used to sample the real environment, and a model consistent with the layout of the actual scene environment is established at the same time, so that the established model is more realistic and the judgment of the test is more accurate.

Further, the specific steps of setting a rule trigger include:

A41: Use Cube in Unity3D to build a cube model;

A42: Add collider components to the created cube model;

A43: Set the cube model property as a trigger in Unity3D, so that the cube model forms a standard trigger;

A44: Mark the position in the initial test scenario model that requires rule judgment as a trigger point;

A45: setting multiple standard triggers respectively through the steps of A41-A43 at each trigger point;

A46: Set parameters and rules for each standard trigger according to the rules of the test item and the scenarios in the initial test scenario model, so that the standard triggers form rule triggers.

Further, said respectively setting a plurality of said standard triggers specifically includes: at each trigger point in the simulated test scenario model, respectively setting said standard triggers at the start, process and end positions of the rule judgment at the trigger point ;

One standard trigger is set at the beginning and the end respectively, and one or several standard triggers are set at the process.

On the simulated test scene model, standard triggers are set at the start, process and end positions of each position that needs to be ruled. The standard trigger set at the start position is used to judge the start of the judgment item, and the standard trigger set at the end position is used At the end of the judging and judging project, the standard triggers set at the process are used to set specific rules, and one or more are set according to the actual situation to judge the rules. It is detailed to each location that needs to be judged, and specific rules are set according to the location to make the judgment more refined and further improve the judgment result.

Setting parameters for each standard trigger includes Position data and Scale data. The position, height and size of the standard trigger can be set according to the Position data and the Scale data.

Wherein the determination rules include preset determination rules;

The preset judgment rules include: speed limit rules, vehicle light rules, line pressure rules and flameout rules.

In addition, the judgment rules also include examination judgment rules;

The examination determination rules include rules set according to examination items.

Compared with prior art, the beneficial effect of the present invention is:

1. The present invention carries out modeling by collecting the data of the test vehicle, and further sets various detailed parameters to the model, so as to realize a finer simulation of the test vehicle, so as to improve the accuracy of the simulation test Effect.

2. The present invention sets rule triggers for each location that needs to be judged by modeling real-time exam scenes, and sets rule triggers for judgment according to the start, process, and end of the judgment, and sets the rule triggers in the process at the same time. The detailed rules of judgment further improve the accuracy of judgment.

3. The present invention establishes conversion rules between the operating equipment of the displayed automobile simulation equipment and the test vehicle simulation model, can obtain more detailed data information of the test vehicle model, further improve the accuracy of judgment and expand the scope of judgment.

Description of drawings

Fig. 1 is a flowchart of the steps of Embodiment 1 of the present invention.

Fig. 2 is a flow chart 1 of the steps of Embodiment 2 of the present invention.

FIG. 3 is a flow chart 2 of the steps of Embodiment 3 of the present invention.

Detailed ways

The accompanying drawings of the present invention are only for illustrative purposes, and should not be construed as limiting the present invention. In order to better illustrate the following embodiments, some components in the drawings will be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, some known structures and their descriptions in the drawings may be omitted. understandable.

Example 1

As shown in Figure 1, this embodiment provides a vehicle simulation model modeling method, the modeling method includes:

S1: Obtain the actual data of the test vehicle, and perform modeling based on the actual data;

S2: Import the modeled vehicle model into the Unity3D project, and add car components to it;

The car components added in this step include: wheel collider, common collider and rigid body component;

Adding a wheel collider is specifically adding WheelCollider wheel collision components to the wheels of the vehicle model in Unity3D to achieve the effect of simulating wheel movement; at the same time, adding a wheel collider to the vehicle model also makes each car wheel concrete, which can Set specific variables and parameters for the wheels by calling the WheelCollider API of Unity3D, such as motorTorque variables, steerAngle variables, breakTorque variables and rpm variables; the motorTorque variable is the motor torque on the axle of the wheel, that is, the forward torque, which is used to adjust the rotation of the wheel ;steerAngle is the steering angle of the wheel, which is used to adjust the steering of the wheel, and it needs to be matched with the input; the variable breakTorque is the braking torque, which is used for the braking of the vehicle model; the variable rpm is the rotational speed of the wheel, which can be used to Calculate the velocity of the vehicle model.

Adding a common collider is specifically adding four spherical colliders of the front, rear, left and right of the vehicle to the vehicle model in Unity3D, and adding a square collider to the body to add a physical collision judgment basis for the vehicle model;

To add a rigid body component is to add a Rigidbody rigid body component to the vehicle model in Unity3D, and set the mass Mass parameter value according to the actual parameter data of the test vehicle, keep the other parameters unchanged, and check the Use Gravity application gravity option of the Rigidbody rigid body component, Simulate the weight of the vehicle so that it has better physics in operation for better simulation results.

S3: Set the vehicle start parameters, gear parameters, power system parameters, vehicle state parameters, engine parameters and input coefficients for the vehicle model with the vehicle components added;

In this step, many parameters are set for the vehicle model, among which:

The starting parameters of the car include: the power off state, the power on state and the starting car state, and the simulated car starting process state is used as the basis for the test judgment.

And/or, the gear parameters include: manual gear parameters and automatic gear parameters;

Wherein, the manual gear parameters include: neutral gear, first gear, second gear, third gear, fourth gear, fifth gear and reverse gear, and the automatic gear parameters include: parking gear, forward gear and reverse gear;

Specifically, the above parameters need to obtain actual parameters from external devices and assign values to them, such as whether the external device is powered on to assign values for the power off state and the power on state, and whether to start the vehicle after the power is turned on To assign a value to the starting state of the car, and then to assign a value to the corresponding gear in the manual gear parameter or the corresponding gear in the automatic gear parameter in the gearing situation of the external device during the starting process. It should be noted that, in this embodiment, the external device is any one in the prior art, which has a complete simulated vehicle operation process and an external simulation device that supports the Unity3D operating system.

And/or, the power system parameters include: the maximum wheel deviation angle, transmission efficiency, brake pedal torque and braking curve; specifically, the maximum wheel deviation angle is different for each vehicle, and needs to be determined according to the actual situation of the test vehicle. Set the parameter data and use it in conjunction with the above-mentioned steerAngle variable to control the steering of the vehicle. The transmission efficiency parameter is mainly to simulate the transmission efficiency of the gearbox of the actual vehicle, so it needs to be set according to the actual parameters obtained from the test vehicle; the brake pedal torque and braking curve are mainly used to simulate the braking of the vehicle and need to be combined with specific inputs. But it needs to be set according to the actual parameter data of the test vehicle, and the braking curve reflects the braking ability of the vehicle.

And/or, the vehicle state parameters include: the gear ratio of each gear, the current torque of the vehicle, the minimum speed and the maximum speed of each gear of the vehicle, the idle speed of each gear of the vehicle, and the foot brake torque;

And/or, the car engine parameters include: maximum engine speed, minimum engine speed, relationship curve between speed and output power, curve speed ratio, idling torque, speed increase limit, speed drop limit, downshift deceleration acceleration, engine to wheel Torque conversion coefficient; the speed ratio of the curve includes the Rpm ratio of the power and RPM curve and the torque ratio of the power and PRM curve; the vehicle state parameters and vehicle engine parameters are used to calculate the speed or braking of the vehicle in each gear, using detailed calculations data, so that the results obtained by using the simulated vehicle of this embodiment to carry out the simulated test are more realistic.

And/or, the input coefficients include: steering wheel input, clutch input, brake input, accelerator input and handbrake switch.

Specifically, the end user operates the corresponding operating device on the external device, such as the steering wheel, clutch and brake, etc., and the external device converts the operation into operation data. In order to facilitate understanding, the operation data is simply expressed in the form of simple values, such as The rotation angle of the steering wheel is converted to (-1, 1). Turning the steering wheel fully to the left is -1, and fully turning the steering wheel to the right is 1; the input of the clutch is converted to (0,1). 1; The input range of the brake is converted to (0,1), the brake is not stepped on to 0, the brake is fully stepped on is 1; the accelerator input is converted to (0,1), the accelerator is not stepped on to 0, and the accelerator is fully stepped to 1; handbrake When the switch is off, it is 0, and when the handbrake switch is on, it is 1; and the value range is matched with the corresponding parameters in the input coefficients in the test vehicle simulation model. In this embodiment, after receiving the operation data input by the external device, the corresponding input coefficient is obtained according to the operation data.

After setting the parameters, proceed to the next step:

S4: Set a speed calculation related method for the vehicle model according to the parameters set in step S3, and obtain a test vehicle simulation model.

Methods related to speed calculation include an ApplyDrive method and a CarSpeed method.

The ApplyDrive method is specifically:

First obtain the current vehicle speed, the current vehicle speed is initially set to 0 when the vehicle model is not started, and then compared with the minimum speed of the current gear of the vehicle model, when the current vehicle speed is less than the minimum speed of the current gear, calculate the current torque of the vehicle , this situation generally occurs when the vehicle starts or shifts up; then the current torque of the vehicle is evenly distributed to the driving wheels to obtain the forward torque of each driving wheel. Vehicles are generally divided into front-wheel drive, rear-wheel drive and four-wheel drive. The actual type distributes the current torque of the vehicle equally to the specific driving wheels. When it is a front drive, divide the current torque of the vehicle by 2 and distribute it to the motorTorque parameter of the front wheels, that is, the forward torque. When it is a rear drive, divide the current torque of the vehicle by The forward torque distributed to the rear wheels after 2, when it is four-wheel drive, divide the current torque of the vehicle by 4 and distribute the forward torque to each wheel; then calculate the rigid body speed of the vehicle according to the forward torque;

The calculation of the current torque of the vehicle is specifically:

The current torque of the vehicle = idling torque * current gear ratio * transmission efficiency * clutch input + torque at the current engine speed * throttle input * clutch input * transmission efficiency;

Among the above parameters, the idle torque, the current gear ratio, and the transmission efficiency can be set according to the actual parameter data of the test vehicle. The clutch input and throttle input are converted from the operation data of the external equipment. The torque at the current engine speed needs to be adjusted. The specific calculation, the specific calculation method is:

The torque at the current engine speed is: divide the current engine speed by the ratio value of the power and speed curve Rpm, bring the result into the speed and output power curve, multiply the obtained value by the torque ratio of the power and speed curve, Multiply this by the engine-to-wheel torque conversion factor to get the torque at the current engine speed. The current engine speed is 0 when the vehicle model is not started, and is given an initial value when the vehicle model is just started, in this embodiment, the initial value is 1000, and then a new value will be obtained through the ApplyDrive method.

In addition, in the calculation of the current torque of the vehicle, when the gear parameter of the vehicle model is automatic, the value of the clutch input is fixed at 1; when the gear parameter of the vehicle model is manual, the clutch input is based on the external The value between (0,1) converted from the clutch pedal of the device is calculated.

After obtaining the current torque of the vehicle, the rotation speed of the wheel can be obtained according to the current torque, and then the vehicle rigid body velocity can be obtained.

In addition, in the ApplyDrive method, the brake input of the vehicle model and the state of the handbrake switch are also obtained to realize the simulation of the brake. Specifically, when the external device steps on the foot brake, the ApplyDrive method obtains the foot brake pedal of the external device. Brake pedal torque (operation data), calculate the foot brake torque according to the brake pedal torque, foot brake torque = brake pedal torque * brake input, and then assign the foot brake torque value to each wheel collision The brakeTorque parameter of the foot brake is used to slow down or stop the vehicle; the handbrake switch is similar to the brake input, the handbrake switch is in two states of on and off, and the maximum value of the brake torque of the foot brake is multiplied by the state value of the handbrake switch (0 or 1). Then assign the obtained value to the brakeTorque parameter of each wheel collider to stop the vehicle.

Furthermore, the ApplyDrive method can also obtain the steering wheel input of the vehicle model to realize the steering simulation. Specifically, when the external device operates the steering wheel, the ratio of the current steering wheel rotation angle to the maximum rotation angle*steering wheel input is used in the future The obtained result is assigned to the steerTorque parameter of each wheel collider, which is the steering of the car.

In addition to setting the ApplyDrive method, this embodiment also sets the CarSpeed method, specifically:

First obtain the normalization of the vehicle rigid body velocity; specifically use the normalized method in Unity3D to normalize the vehicle rigid body velocity into a vector with direction, and then calculate the speed direction obtained by normalizing the vehicle rigid body velocity and The speed of the rigid body of the vehicle is the same;

Then define a minimum speed limit for the current gear. The minimum speed limit for the current gear is used to limit the minimum speed limit of the vehicle model in the current gear during operation. The calculation of the minimum speed limit for the current gear is specifically: the minimum speed limit for the current gear Speed = (maximum speed of the current gear - minimum speed of the current gear) * throttle input + idle speed of the current gear; the minimum speed of the current gear is affected by the throttle input.

When the value of the rigid body speed of the vehicle is greater than the maximum speed of the current gear, the current vehicle speed is calculated, specifically:

The current vehicle speed = the maximum speed of the current gear * the normalization of the vehicle rigid body speed; and update the vehicle rigid body speed to the current vehicle speed; it is equivalent to the current vehicle speed cannot exceed the maximum speed of the current gear.

When the value of the rigid body speed of the vehicle is greater than the minimum speed limit of the current gear and less than the maximum speed of the current gear, the intermediate speed speedVal is defined, and the calculation formula of the speedVal is: vehicle rigid body speed-downshift deceleration acceleration*time; The time is the interval from the last frame to the current frame, in seconds; the current vehicle speed = the value when speedVal is greater than 0 * the normalization of the vehicle rigid body speed; and update the vehicle rigid body speed to the current vehicle speed; ApplyDrive according to the above settings Calculation of the method, when the accelerator input is reduced, the current torque of the vehicle decreases, and the speed of the rigid body of the vehicle decreases, that is, the speed of the vehicle model in the current gear is affected by the accelerator input, so define speedVal to simulate the process of decelerating the vehicle at this stage; But when the vehicle is running, even if there is no accelerator input, the vehicle will not stop running directly. In order to further simulate the real running situation of the vehicle, the minimum speed limit of the current gear is used to limit the minimum speed of the vehicle model running in the current gear; according to The calculation formula for the minimum speed limit of the current gear, when there is no throttle input, the minimum speed limit of the current gear is the idle speed of the current gear, that is, when there is no throttle input, the speed of the rigid body of the vehicle will decrease, but the minimum speed will be reduced to the minimum idle speed of the current gear ;When there is throttle input, even if the speed of the rigid body of the vehicle decreases, the minimum speed can only be reduced to the minimum speed of the current gear=the maximum speed of the current gear-the minimum speed of the current gear)*throttle input+idle speed of the current gear;

Then calculate the current normalized speed of the vehicle, specifically, the normalized speed of the vehicle*3.6, and normalize the current speed of the vehicle into a unit of km/h. At the same time, since the previous time calculation unit is seconds, and the vehicle speed unit is usually km/h, it is necessary to standardize the current vehicle speed after calculation, and convert the current vehicle speed unit to km/h to obtain the vehicle The current normalized velocity.

Example 2

As shown in Figure 2, the present embodiment provides a method for judging a vehicle simulation test, using the test vehicle simulation model established by the vehicle simulation model modeling method of Embodiment 1, the method comprising:

A1: Create an initial test scene model based on the real test scene and import it into Unity3D;

In this step, the actual test scene is sampled through aerial photography modeling or oblique photography technology, and the sampling results are processed and optimized by Maya3D to obtain an initial test scene model that is one-to-one with the actual scene.

A2: use the vehicle simulation model modeling method to establish a test vehicle simulation model according to the information of the test vehicle;

A3: According to different test items, set the rules of the test items;

A4: Set rule triggers and judgment rules for the initial test scenario model according to the rules of the test item, and generate a simulated test scenario model;

Specifically, as shown in Figure 3, setting the trigger includes the following steps:

A41: Use Cube in Unity3D to build a cube model;

A42: Add collider components to the created cube model;

A43: Set the cube model property as a trigger in Unity3D, so that the cube model forms a standard trigger;

A44: Mark the position in the initial test scenario model that requires rule judgment as a trigger point;

A45: Set multiple standard triggers at each trigger point through the steps of A41-A43, wherein one standard trigger is set at the start and end positions of the rule judgment at the trigger point, and one standard trigger is set at the end position of the rule judgment or multiple standard triggers, and set the number of standard triggers that need to be set according to the rules that actually need to be judged;

A46: Set parameters and rules for each standard trigger according to the rules of the test item and the scenarios in the simulated test scenario model, so that the standard triggers form rule triggers, where the parameter rules include Position data and scaling Scale data for setting The size and position of the trigger determine that the test vehicle simulation model can meet the rule trigger for rule judgment.

In a specific implementation, for example, in the project of a right-angle turn, the right-angle turn in the initial test scene model needs to be used. Set a rule trigger on the turning start position of a right-angled curve as the start trigger of the right-angled turn project, and set the parameters of the start trigger, where the Position data is: x=-46.9, y=1.77, z= 5.89, the zoom Scale data is: x=1.84, y=4.96, z=11.22, and set trigger rules for it at the same time: determine whether to turn on the turn signal; set a rule trigger at the end position of the turn as the end trigger of the right-angle turn project , and set the parameters of the end trigger, where the Position data is: x=3.6, y=4.4, z=30.2, the scaling Scale data is: x=16.11, y=7.82, z=1.8, and set the trigger for it at the same time Rules: Determine whether to turn off the turn signal; when the test vehicle simulation model passes through the right-angled curve, it collides with the start trigger, and the system triggers the callback OnTrggerEnter(Collidercollider) method to feed back the judgment result of the start trigger; when the test vehicle simulation model When leaving a right-angled curve, it collides with the end trigger, and the system triggers the callback OnTrggerEnter(Collider collider) method to feed back the judgment result of the end trigger. Each rule trigger is placed in an ideal position of the initial test scene model, and the ideal position is determined according to the actual content to be judged, so as to ensure that the test vehicle simulation model can meet the rule trigger to trigger the judgment.

A5: Import the simulated test scene model and the test vehicle simulation model with set rule triggers and judgment rules into the external car simulation equipment system, and match the test vehicle simulation model with the operating equipment in the car simulation device to establish The conversion rules of the operation data of the operation equipment and the simulation data of the test vehicle simulation model;

A6: The terminal user inputs the operation data through the operation device, and the vehicle simulation device converts the operation data into the simulation data of the test vehicle simulation model according to the conversion rule;

It has been described in Embodiment 1 that after the test vehicle simulation model is imported into the vehicle simulation device, the operation data can be converted into simulation data corresponding to the test vehicle simulation model parameters by operating the operating device of the peripheral vehicle simulation device, When the test vehicle obtains the corresponding simulation data, the control function is called to drive its operation. It is worth noting that, in this embodiment, the car simulation device is any one of the prior art, which has a complete simulated vehicle operation process and a car simulation device supporting an operating system of Unity3D.

A7: The car simulation device drives the test vehicle simulation model to run in the simulated test scene model according to the simulated data, and judges the result according to the rule trigger and the judgment rule.

Specifically, the determination rules include preset determination rules and examination determination rules;

The default judgment rules include the following rules:

Speed limit rules, the specific speed limit rules are that the speed of the vehicle cannot exceed the specified speed;

Car light rules, the use of turn signals when turning, turning around and changing lanes, judge according to whether the TurnSignal feedback of the test vehicle simulation model is true;

Line pressure rule, set the rule trigger as whether the collider on the test vehicle simulation model touches the rule trigger or crosses the rule trigger, and feedbacks the test vehicle simulation model pressure line when it touches or crosses;

Flame-off rules, the test vehicle simulation model cannot be turned off during the test, and the judgment is based on the fact that the vehicle start-up parameter feedback of the test vehicle simulation model is the state of starting the car and the current speed feedback of the vehicle is greater than 0.

In this embodiment, other preset judgment rules are also included for judging whether the test or the vehicle is running normally and in accordance with the rules.

The examination determination rules include specific rules set according to examination items.

In a specific implementation mode, if the test content of subject three includes the project of passing through the school road section, the criteria for judging whether the project is qualified is that the brakes need to be tapped twice, and the speed of the vehicle cannot exceed 20km/h. In order to realize the determination of these two rules. At the beginning of the project, when the start trigger of the project judgment is encountered, the current speed of the simulated car is obtained every frame to determine whether the speed exceeds 20km/h. If it exceeds, a prompt will pop up and the corresponding points will be deducted. . At the same time, the depth data of the brake pedal should also be recorded in each frame. Specifically, at the beginning of the project, a temporary array is created and the data is written into it. After the project end event is triggered, the The end trigger of project judgment analyzes the data in the temporary array to judge whether the value of the data has a trend of changing from large to small twice. If not, a prompt will pop up and the corresponding points will be deducted. In this embodiment, the determination of other examination-related items is also included, which needs to be set according to the determination content of the actual examination.

Apparently, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the technical solution of the present invention, rather than limiting the specific implementation manner of the present invention. Any modification, equivalent replacement and improvement made within the spirit and principle of the claims of the present invention shall be included in the protection scope of the claims of the present invention.

Claims (10)

1. A vehicle simulation model modeling method, characterized in that the modeling method comprises:

s1: acquiring actual parameters of the test vehicle, and modeling according to the actual data;

s2: importing the modeled vehicle model into a Unity3D project, and adding an automobile component to the model;

s3: setting automobile starting parameters, gear parameters, power system parameters, automobile state parameters, engine parameters and input coefficients for a vehicle model added with automobile components;

s4: and (3) setting a speed calculation related method for the vehicle model according to the parameters set in the step (S3) to obtain the test vehicle simulation model.

2. The method according to claim 1, wherein the vehicle component in step S2 comprises: wheel collider, common collider and rigid body assembly;

the addition of the wheel impactor specifically includes: wheel collision assemblies are respectively added for wheels of the vehicle model in the Unity 3D;

adding a common impactor specifically includes: adding four spherical colliders of a head, a tail, a left and a right of a vehicle and a square vehicle body collider for a vehicle model in Unity 3D;

the adding of the rigid body component specifically comprises: and adding a Rigidbody rigid body component to the vehicle model in the Unity3D, setting a quality Mass parameter value according to actual parameter data of the test vehicle, and checking a Use grade application Gravity option of the Rigidbody rigid body component.

3. The vehicle simulation model modeling method according to claim 1, wherein the vehicle start-up parameters in the step S3 include: a power-off state, a power-on state, and a start-up vehicle state;

and/or, the gear parameters include: manual gear parameters and automatic gear parameters;

wherein, manual gear parameters include: neutral, first gear, second gear, third gear, fourth gear, fifth gear and reverse gear, the automatic gear parameters include: a parking gear, a forward gear and a reverse gear;

and/or, the powertrain parameters include: maximum wheel offset angle, transmission efficiency, brake pedal torque, and brake profile;

and/or, the vehicle state parameters include: gear ratio of each gear, wheel torque, minimum speed and maximum speed of each gear of the vehicle, idle speed of each gear of the vehicle and foot brake torque;

and/or, the automobile engine parameters include: maximum engine speed, minimum engine speed, speed-to-output power relationship curve, curve speed ratio, idle torque magnitude, speed-up limit, speed-down acceleration, engine-to-wheel torque conversion coefficient;

and/or, the input coefficients comprise: steering wheel input, clutch input, brake input, throttle input, and hand brake switch.

4. A vehicle simulation model modeling method according to claim 3, wherein the speed calculation-related method in step S3 includes an ApplyDrive method;

the ApplyDrive method specifically comprises the following steps:

when the current vehicle speed is smaller than the minimum speed of the current gear, calculating the current torque of the vehicle, and equally distributing the current torque of the vehicle to driving wheels to obtain the forward torque of each driving wheel, and calculating according to the forward torque to obtain the rigid body speed of the vehicle;

the driving wheels are wheels for the vehicle to actually drive the vehicle to advance;

the vehicle rigid body speed is a theoretical speed of the vehicle model.

5. The method for modeling a vehicle simulation model according to claim 4, wherein the calculating the current torque of the vehicle is specifically:

vehicle current torque = idle torque magnitude current gear ratio transmission efficiency clutch input + torque at current engine speed clutch input transmission efficiency;

the torque at the current engine speed is calculated according to the parameters of the automobile engine.

6. The modeling method of a vehicle simulation model according to claim 5, wherein the velocity calculation-related method in step S3 further includes a carteed method;

the CarSpeed method specifically comprises the following steps:

obtaining normalization of the rigid body speed of the vehicle;

calculating the lowest speed limit of the current gear, wherein the lowest speed limit of the current gear is = (the maximum speed of the current gear-the lowest speed of the current gear) is the throttle input plus the idle speed of the current gear;

when the value of the rigid body speed of the vehicle is larger than the maximum speed of the current gear, the current vehicle speed is calculated, specifically:

current vehicle speed = current gear maximum speed x vehicle rigid body speed normalization; and updating the vehicle rigid body speed to the current vehicle speed;

when the value of the rigid body speed of the vehicle is larger than the lowest speed limit of the current gear and smaller than the maximum speed of the current gear, defining an intermediate speed speedVal, wherein the calculation formula of the speedVal is as follows: numerical value of vehicle rigid body speed-downshift deceleration acceleration time; the time is the interval from the last frame to the current frame, and the unit is seconds; normalizing the vehicle rigid body speed by a value when the current vehicle speed = speedVal is greater than 0; and updating the vehicle rigid body speed to the current vehicle speed;

then, calculating the current standardized speed of the vehicle, specifically, the current speed of the vehicle is 3.6, and the current speed of the vehicle is standardized to be the unit km/h.

7. A vehicle simulation test judgment method, characterized in that a test vehicle simulation model established using a vehicle simulation model modeling method according to any one of claims 1 to 6, the method comprising:

a1: establishing an initial examination scene model according to a real examination scene and importing the initial examination scene model into Unity 3D;

a2: establishing an examination vehicle simulation model according to the information of the examination vehicle by using the vehicle simulation model modeling method;

a3: setting rules of the test items according to different test items;

a4: setting a rule trigger and a judging rule for the initial examination scene model according to the rule of the examination item, and generating a simulated examination scene model;

a5: the method comprises the steps of importing a simulated examination scene model and an examination vehicle simulation model with set rule triggers and judging rules into a system of external automobile simulation equipment, matching the examination vehicle simulation model with operation equipment in the automobile simulation equipment, and establishing operation data of the operation equipment and conversion rules of simulation data of the examination vehicle simulation model;

a6: the terminal user inputs operation data through the operation device, and the automobile simulation device converts the operation data into simulation data of an examination vehicle simulation model according to the conversion rule;

a7: the automobile simulation equipment drives the test vehicle simulation model to run in the test scene simulation model according to the simulation data, and judges the achievement according to the rule trigger and the judging rule.

8. The method for determining a simulated test of a vehicle according to claim 7, wherein the establishing an initial test scene model based on a real test scene is specifically as follows:

sampling a real examination scene by using aerial modeling or oblique photography technology, and processing and optimizing a sampling result by using Maya3D to obtain an initial examination scene model consistent with the environment layout of the actual scene.

9. The method for determining a vehicle simulation test according to claim 7, wherein the setting rule trigger comprises the steps of:

a41: cube models are built in Unity3D using Cube;

a42: adding a collider component to the established cube model;

a43: setting a cube model attribute as a trigger in the Unity3D, so that the cube model forms a standard trigger;

a44: marking a position needing rule judgment in the initial examination scene model as a trigger point;

a45: setting a plurality of standard triggers through the steps of A41-A43 at each trigger point;

a46: parameters and rules are set for each standard trigger according to the rules of the test items and the scenes in the initial test scene model, so that the standard triggers form rule triggers.

10. The vehicle simulation test judgment method according to claim 6, wherein the setting of the plurality of standard triggers respectively includes: at each trigger point in the simulated examination scene model, setting the standard trigger at the starting, process and ending positions of rule judgment at the trigger point;

wherein a standard trigger is set at the beginning and the end, respectively, and one or several standard triggers are set at the process.

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